#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
//#define int long long
#define pb push_back
#define ff first
#define ss second
using namespace std;
const int N=555;
char a[N][N];
int n,m,d[N][N];
int xx[4]={1,0,-1,0};
int yy[4]={0,1,0,-1};
//c1 aris
//c2 gvinda
int rot(int x2,int y2,int m1,int m2){
char c1=a[x2][y2];
char c2;
if(m1==1)c2='S';
if(m2==1)c2='E';
if(m1==-1)c2='N';
if(m2==-1)c2='W';
if(c1==c2)return 0;
string c3="";c3+=c1;c3+=c2;
//cout<<c3<<" ";
if(c3=="NE" or c3=="ES" or c3=="SW" or c3=="WN")return 1;
if(c3=="NS" or c3=="EW" or c3=="SN" or c3=="WE")return 2;
if(c3=="NW" or c3=="EN" or c3=="SE" or c3=="WS")return 3;
}
void dijkstra(){
d[0][0]=0;
priority_queue<pair<int,pii>,vector<pair<int,pii>>,greater<pair<int,pii>>>pq;
pq.push({0,{0,0}});
while(pq.size()){
auto st=pq.top();
pq.pop();
int x=st.ss.ff;
int y=st.ss.ss;
int d1=st.ff;
if(a[x][y]=='X')continue;
for(int i=0;i<4;i++){
int xn=x+xx[i];
int yn=y+yy[i];
if(xn<0 or xn>n-1)continue;
if(yn<0 or yn>m-1)continue;
int r=rot(x,y,xx[i],yy[i]);
if(d1+r<d[xn][yn]){
d[xn][yn]=d1+r;
pq.push({d[xn][yn],{xn,yn}});
}
}
}
}
int main(){
ios_base::sync_with_stdio(NULL);cin.tie(NULL);
cin>>n>>m;
for(int i=0;i<n;i++){
for(int j=0;j<m;j++){
d[i][j]=1e9;
cin>>a[i][j];
}
}
//cout<<rot(0,0,0,1);
dijkstra();
// for(int i=0;i<n;i++){
// for(int j=0;j<m;j++){
// cout<<d[i][j]<<" ";
// }cout<<endl;
// }
if(d[n-1][m-1]==1e9)cout<<-1;
else cout<<d[n-1][m-1];
}
